Forwardly movable vehicle seats of this kind are mainly in use in vehicles having but one door on either side. They facilitate access to a back seat while boarding the vehicle through the only side door. When the vehicle seat is moved forward, access to the back seat located behind is facilitated.
Such type vehicle seats have to meet the requirement of being readily and safely forward movable in mechanical terms. This forward movement is initiated by actuating the disengagement lever which releases the normally locked seat back hinge. The then enabled forward tilt of the seat back causes the two catch devices to be released so that the seat may be moved forward within the pairs of rails of the longitudinal adjusting device. If the seat is moved back thereafter, the initial position has to be found again. This is achieved by means of the memory mechanism. Said memory mechanism ensures that the seat is only allowed to move back as far as the initial position.
A forwardly movable vehicle seat of the type mentioned herein above is known from EP 0 844 133 B1. Similar forwardly movable vehicle seats are also known from U.S. Pat. No. 5,893,610, DE 107 597 111 C1 and DE 197 571 110 C1.
The following problem may possibly arise with such type forwardly movable vehicle seats: the catch devices are unlocked both through the pivotal movement of the seat back and through actuation of the actuation lever. Accordingly, two different devices may act upon the catch devices. Problems may arise when, one device having already unlocked the catch devices, the second device is knowingly or unknowingly actuated as well. The objective of the invention is to avoid the disadvantages resulting therefrom. More specifically, the objective of the invention is to avoid damage due to maloperation, in particular to prevent damage to the driver mechanism as a result of maloperation of the actuation lever.
When the seat back is folded forward, the catch devices are unlocked. In order to allow maintaining the catch devices in the unlocked condition, the driver mechanism must remain active, that is, it must for example be under tension. The driver mechanism comprises for example a sheathed cable that may e.g., be configured to be a Bowden cable. If said sheathed cable is tense, such a condition being provided when the seat back is folded forward, and if the actuation lever is pushed at the same time, meaning, is pivoted in a direction counter to the direction in which, when actuated, it is in a normal limit stop position, said sheathed cable is overtensioned. The cable itself, its fastening means or other parts of the driver mechanism may be destroyed thereby. Usually, the actuation lever is located beneath the front edge of a seat, normally it slightly protrudes therefrom. It is connected to the transverse bar through quite long a lever arm. As a result, quite high a force may be exerted onto the transverse bar, and as a result thereof, onto the driver mechanism as well.